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Cons{der!ng n^ar runoff reaches a wer.and bom from a storm sewer and <br />from Qd;acent upiards. the following tnreo issues will be ncnoged to <br />mininrVze impact from ajnoff: <br /><• Bounce - deals with the volume of stormwater input, in te-ms of the <br />change in water levels and the duration o' *nat change. Ponds w ii <br />be desigr^d to monoge bounce assocated with runoff from storm <br />sewers. Based a runoff event w;th a 100-year recurrence mtervc!. <br /><• Phosphorous (P) - addresses the amount of phosphorous oe^ng <br />delivered to a given wercnd via ajnoff from storm sewers <br /><• Buffer • addresses bom the quality orTd qucnnty/rote of runoff <br />enterfrg a wetland as surface flow from odjocent upionds. <br />Protection <br />Classincation Protection Strategy <br />j Protettl <br />Bounce: Maintain boonce at or below existing cenditiors <br />P‘: Umit loadings to predevelopment loading (O.W Lbs/Ac/Yr) <br />1 Buffer 50 fzzt wide h <br />Bounce: Mainta n bounce ac or below tidstlnfl condioors olus Q.S foot <br />Protect II P: Limit loadings to predevelopment loadings times 2 f0.2B Lbs/Ac/Vr) <br />Buffer 35 feet wide <br />Bounce: Maintain bounce at or below eidstno conditions olus i.o font | <br />Protect III1 P: Limit concentration to predeveicpment concentrations (200 opb) | <br />1 Buffer 25 feet wde <br />Bounce: No Quantity retjuirement <br />Utilize P: Limit concentration to 225 ppb <br />^ P ■ phesphofous <br />Buffer 15 feet wide * <br />The aty of Orono has taken a somewhat different approach to the sizing <br />and location requirements for wetlarxj buffers, for a couple of reasons <br />1 . It is generally known that, ossurnng dl things equal, a Jcrgef <br />waterbody has a greeter assimilative copodty then a small <br />wetlor^. l.e. some given amount of phosphorous con be more <br />easay "absorbed' by a 14 ocre marsh than by o 0.8 ocre fen. <br />2. A given wetiorjd's rur»off susceptibility roting Js a good ihacctor of it's <br />overall quality in terms of its functions and values. Sensitive <br />communities with a diverse assemblage of plants provide sco'ce <br />and/or high quaSty habitat (remember. Protecticn Clossiflcotions ore <br />tied to runoff susceptibility). <br />atrof Orono